Episode 1 Trust Me, I'm a Doctor

We are constantly being told how to live our lives.

But what's the health advice you can really trust?

In this series, we use our expertise to guide you

through the contradictions and the confusion.

We'll get to the heart of the debate.

And ensure you get the information you need.

We're here when you don't know where to turn.

I'm Michael Mosley. In this series, I'm joined by a team of doctors.

Together, we'll cut through the hype, the headlines, and the health claims.

This is Trust Me, I'm A Doctor.

It's a new year and a new you.

So welcome to a special edition of Trust Me, I'm A Doctor,

coming from Manchester,

a city where apparently people have increased their activity

levels more in the last year than anywhere else in the UK.

To welcome the New Year, we start with a cheat's guide to exercise.

We'll show you how to burn more fat without more effort,

how to tone up your body without hitting the gym.

You can make it harder by going slower.

We'll discover what detoxing really does to you,

which festive leftovers you shouldn't reheat,

and a blind woman sees in the New Year thanks to a bionic eye.

Oh, my God!

But first...

As a medical journalist, I'm well aware of the benefits of exercise.

But I also know that most people do not come remotely close to

doing the recommended levels.

So in this edition, we're going to be looking at ways to get

the maximum benefit with the minimum effort.

At this time of year, the get-fit message is everywhere.

Along with lots of things that supposedly help.

So Dr Chris van Tulleken has been tracking down the truth

behind one of the most popular fitness products out

there on the market.

A lot of people use a protein supplement drink.

Those drinks are made of this stuff.

This is protein powder.

Protein supplements became popular in California in the '70s and '80s.

Once the preserve of giant bodybuilders,

today they're sold to everyone

to keep protein levels up and avoid muscle wastage as we grow older.

And the marketing is working.

Today, it's a £7 billion industry worldwide,

with one in 20 taking them in late-middle age.

But are we all being conned out of our money?

Do you actually need more protein in your diet?

To find out, I've come to Glasgow

to put protein supplements to the test.

The tempting theory behind supplements is that the protein

in them goes straight into your muscles,

keeping all of us in youthful vigour.

All this is based on the idea that powders like this provide

protein in a form that your muscles find easy to use, but is that true?

Time for me to put in some effort

under the supervision of Dr Stuart Gray.

That is the proper burn. That is the full leg on fire.

Keep it going. Keep pushing.

I'm done. I'm done.

Thanks, Stu.

So now I'm going to drink a supplement drink

and if what the manufacturers claim is true,

then the protein from the drink is going to go

straight into my muscle and this protein drink has a twist

because the proteins in it are labelled chemically,

so we can trace them as they go from my mouth to the muscle. Right.

Just drink this?

To trace the proteins from the drink,

we actually need to look inside my leg muscles.

Look away now if you're squeamish.

Oh, my Lordy!

Because unfortunately for me,

that means a very large needle to take a sample from deep in my leg.

I've only exercised one leg,

so Stuart's taking a sample from the other leg, too, as a control.

Then he can compare the two.

Do proteins from supplements actually go into our muscles at all?

And if so, does it happen more when we're exercising?

-Was it worth it? Did you get a result?

-We did, yes.

What we saw was because we had labelled the protein that

was in the drink, we could trace its movement through the body.

So we saw it going into the muscle samples that we took from your legs.

Really? That's quite surprising to me.

Relatively quickly, as well.

Because we only... Two or three hours we took the biopsy samples.

It can quite quickly get into your muscle, yeah.

And the key question, I guess, is did more of it end up in this

leg which I exercised than in the other leg, which I didn't?

It did, yes. So we had about 13% more of the labelled protein going

into the exercised leg compared to your leg that you'd rested.

Why does this muscle, when it has been exercised, need more protein?

I'm sure, as you felt, when you exercised that muscle,

it was painful. It was tired. So you caused slight damage to that muscle.

It's all part of the process of building new muscle,

so you slightly damage it and it is then repaired and it becomes...

It is repaired bigger and stronger.

I think that's really surprising.

It's almost like Popeye, isn't it?

You know, I eat the thing and then my muscles get bigger.

So at first glance, there seems to be an unquestionable logic.

The proteins go straight from the drink into our muscles, so they

must be getting a boost, but for me that's not the end of the story.

At Trust Me, I'm A Doctor, we're

deeply suspicious of any claims of unquestionable scientific logic.

So we're going to put protein supplements to the test.

Do they really give you bigger, stronger muscles?

Find out later in the programme,

when we'll be doing a proper trial to find out once and for all.

Exercise is something we hear a lot of at this time of year.

We're told we should do at least 150 minutes of exercise a week.

On top of that, the NHS recommends doing a couple of sessions

of resistance exercise a week to build and maintain strength.

Resistance exercises improve muscular fitness.

But they have limited appeal.

Do you fancy some weight training? A little bit of weights?

Do you fancy some weight training?

Weights? No.

I think most people find the idea of pumping iron rather intimidating.

Plus not that many people actually want bulging biceps, so how can

you get the benefits of resistance exercise without going down the gym?

The benefits we are after have nothing to do with a washboard

stomach or a sixpack.

Sadly, as we enter our 40s, our bodies get worse at building

and maintaining muscle.

So as we get older, we get weaker.

But how bad does it get?

At the University of Nottingham, Dr Philip Atherton is going to

take a peek inside my 58-year-old thigh.

-If I move around a bit?

-If you contract there, you can

actually see that the muscle fibre angles sort of change and tip

and that is the sort of contraction of the muscle.

That's cool. I've never seen that before.

So if I don't do anything much with

it from my age now, that' just going to get smaller, is it?

-Essentially, given that you're 50 now, Michael...

-50+.

-50+, OK.

..you would be expecting in essence to lose around 5% on average

of muscle mass per decade. It could even exceed that.

This is the time at which muscle really,

really starts to decline in mass, so what we would expect to see is

if we were to measure this decade by decade, we would probably see

that that muscle would get thinner and thinner over time.

From the age of 40,

we can lose up to 1% of our muscle mass every single year.

And that loss affects more than just our strength.

If you look in very, very large-scale studies,

one of the best predictors of poor health in older age

and even early death is actually muscle mass.

It's all sounding rather depressing. But there is some good news.

The right exercises can slow, even reverse, this decline in strength.

But do you have to hit the gym to do it?

Or is there an easier way?

With a group of intrepid volunteers, we're going to find out.

They're all the wrong side of 40 and at risk of losing their muscles.

We begin by testing their strength.

And push, push, push, push! Keep going, keep going, keep going!

These machines measure how strong their legs are

and how much power they can release in one go.

Ultrasound tells us how big their thigh muscles are.

And we're also testing their grip strength.

Together, these readings give us

a good indication of whole body strength.

And now, we're ready to see if we can turn back time

and build muscle without any special equipment.

Our volunteers have been given a set of exercises

which are designed to fit in seamlessly with their domestic lives.

Let me demonstrate.

These are bicep curls with ordinary sort of household items -

in this case, bags of flour.

This is a classic exercise, the lunge.

Except it's done while you're vacuuming.

This is a toothbrush squat.

The idea is that you're working some of the biggest muscles in the body,

those in your bottom, and you can make it harder by going slower

and obviously by doing more.

Our volunteers carry out a set of eight exercises every day,

working muscles all over their bodies.

But will this DIY approach to resistance training really

make a difference?

With a month up, it's time to find out.

We measure their strength and thigh muscle thickness again.

And the results have certainly surprised muscle expert

Dr Philip Atherton.

OK. So, moment of truth.

Whether those four weeks have actually been worth doing.

I'm very intrigued. Where are we, then?

So what we found with the group is basically there was a 3%

increase in the cross-sectional area of the leg muscles.

OK. 3%? Yeah, yeah.

They haven't started to look like bodybuilders,

and they're more toned.

But have they become stronger, the important measure?

We looked at leg strength and we were able to detect an increase,

and, again on a group basis, this was about 12%.

Ooh, yeah. We like that.

-12% is a big number.

-Yeah, absolutely.

This is again a marked increase in leg strength

and following that as well...

Do you think that was the squats?

I think it could have been very much part of the reason why

their strength increased.

But interestingly, the power increase is similar to the muscle

strength in that it increased 13% as a group.

Wa-hey! So you're all dynamos.

Can you feel that energy just surging through you now, that power?

So a 3% increase in the area of the muscle led to a 12%

increase in muscle strength,

and a 13% increase in power output.

And their grip strength also increased by 4%.

I think that's quite incredible.

Proof that our home training programme has really worked.

I must admit, I am astonished that in four weeks you can see such

big changes, particularly in things like power.

I understand the other ones kind of matter, but that is big.

Did you find it OK?

Yes. Yes, you could incorporate it into your daily routine.

Do you think you will continue?

Yes. Certainly will do.

Especially with the results.

The results of these no-sweat exercises have

delighted our volunteers.

I do feel stronger.

I do feel fitter after the programme,

and I intend to keep it on.

They are now stronger, fitter, and more resilient.

And all our exercises can be done for free in the privacy of your own home.

They can even be done while you're watching the telly.

There is a full list of the exercises

and the proper instructions on our Trust Me website.

And now surgeon Gabriel Weston is in the New Year spirit.

And what better way to start off a January health kick than with

juices and smoothies?

The biggest claim they make is that they're full of antioxidants.

But does that really mean they're good for us?

The message written on the side of this carton feels very clear.

Oxidation causes damage to your cells and that if you

drink lots of this antioxidant juice, it will protect them.

But is that actually true?

Antioxidants are meant to mop up free radicals,

byproducts of chemical reactions in our cells.

Now, for many years, free radicals have been thought to cause

an accumulation of damage to cells,

possibly even reducing our lifespan.

So taking extra antioxidants should help combat this.

But does it?

We want to test whether juices

and smoothies really do live up to the hype.

So first, just how powerful is their antioxidant kick?

Newcastle University are analysing some for us,

and comparing them with some bog-standard orange juices.

And the results are surprising.

First up, the orange juices.

Then, a fresh super-fruit smoothie - twice the price,

but no more antioxidants.

Next, two brands of smoothies specifically

marketed for antioxidants.

Still no better.

Finally, a superfood smoothie, a whopping three times

the antioxidant power of any of the others.

So what's going on?

Antioxidants might have an air of mystery about them, but if you look

at the label on the side of one of these drinks, it's clear that most

of the antioxidant effect is just coming from plain old vitamin C.

Vitamin C is actually a powerful antioxidant.

It's found naturally in most fruit and veg,

but is also a common additive to stop juice going brown.

There's nothing special about fruits themselves in these drinks.

So my next question is, do the antioxidants in these drinks

actually do anything inside our bodies?

To find out,

we recruited ten volunteers to do an experiment never attempted before.

Under the guidance of Dr Kirsten Grant,

they all drank 360ml of smoothie.

We measured the antioxidant status of each person's blood

beforehand so we had a baseline,

and then regularly over the next 24 hours.

Did the smoothie give them an antioxidant boost?

Well, at first, the antioxidant levels in their blood did go up,

only to plummet dramatically after 4-5 hours.

And they even went well below baseline

and were only just coming back to baseline after 24 hours.

Kirsten was not surprised by the sudden drop to below baseline,

as our bodies actually work to keep everything in perfect balance,

including antioxidant levels.

This balance where the body will keep the level constant,

it's called homeostasis, and it's the same for our temperature,

for our sugar levels,

for everything else in the body that should have a correct level.

Our bodies continually produce their own antioxidants.

When we take in a big extra dose,

our bodies slow down that production to get back to the optimum level.

But what Kirsten had not expected was that it would take so long.

For almost a day after drinking just a big glass of smoothie of juice,

our volunteers' blood contained less antioxidant power than normal.

It's the opposite effect from what most of us would expect.

And lower antioxidant levels presumably mean more free

radicals in our bodies.

But Kirsten thinks the messages we get from the adverts are even

more misleading,

as free radicals are not such a bad thing.

So it isn't the case that all of us have got our bodies

full of bad free radicals and the more we slosh the smoothie in,

the more they're going to mop up those bad things in our body?

No. Normal, healthy people have

exactly the free radicals that they need.

Free radicals are actually quite important.

For example, they are one of the signal molecules that tells the

cells in our body when you need to repair, for example, muscle fibres.

So if you want to go to the gym and do some training,

if it wasn't for the free radicals, your muscles wouldn't grow.

The science and the marketing are poles apart.

Your body makes exactly the antioxidants it needs

and taking in a big dose merely throws it out of balance.

While there's excellent evidence that eating fruit and vegetables

is good for you, the benefit isn't coming from the antioxidants.

So ignore the marketing hype, banish the detox myth,

and stop wasting your money on all those fancy smoothies and juices.

We contacted two leading smoothie manufacturers, who said their

products were a convenient way of getting more fruits

and vegetables at a time when only a third of the UK

population are getting their five a day.

They're confident that the vitamins

and minerals in their antioxidant recipes contribute to

the protection of cells from oxidative stress,

a claim that is supported by specific European regulations.

Their statements are published in full on our website.

Now, for most people, the point of doing exercise is to burn excess fat.

But what if you could do that without any extra effort at all?

Well, we've decided to take some tantalising new research

out of the lab and put it to a real test for the very first time.

Over to Dr Saleyha Ahsan.

For most of us,

losing the spare tyre can be a bit of an uphill struggle.

But is there a smarter way of turning our bodies into more

efficient fat-burning machines,

not by exercising more, but by changing the time that we do it?

We've come across some brand-new research at the University

of Surrey that suggests to burn more fat, you don't need to

change your diet or how much exercise -

the secret is knowing when to eat and when to exercise.

First, brother and sister Josh and Jess are going to be tested

under lab conditions as they exercise on an empty stomach.

Neither has eaten since yesterday evening.

So are you hungry?

-Starving.

-Ravenous.

But before they eat, they'll do half an hour of exercise and

Dr Adam Collins is going to measure how much fat their bodies burn.

And you're off.

This looks a bit complicated.

Well, what we're monitoring here is the fuels that are

burning during exercise, so when you're exercising, you

are using a combination of glucose, which is a carbohydrate, or fat.

You can see, he's got a face mask there

and we're sampling the air that he's breathing in and out.

In particular, we're looking at the oxygen that he's breathing in

and the amount of carbon dioxide he's breathing out.

And with those two things, we can work out how much fat he's

burning and how much carbohydrate he's burning.

So our body uses two different types of fuel.

Carbohydrate and fat.

And what we're interested in is the fat burn,

because that's what's key to losing the spare tyre.

Today, we're measuring how much fat Josh is burning

when he exercises before he eats.

Josh, how are you doing?

-I'm alive.

-You're alive.

He's still talking, which is good.

After 30 minutes, it's Jess' turn to jump on the bike.

But Josh isn't finished.

So what we're interested in is the impact of exercise after

the exercise is finished.

Because that's when you do most of your fat burning,

so most of the effect of that exercise actually

happens in the period after the exercise rather than during it.

-Tuck in. Breakfast.

-Thank you.

Now, Josh gets some breakfast.

It's in the form of a drink

so that the calories can be precisely controlled.

Meal over, Adam continues to measure how much fat Josh is

burning now that he is no longer exercising.

So that doesn't look very relaxing.

It's good.

-It's very calming underneath there.

-OK.

And 30 minutes later, with her exercise complete,

it's Jess' turn for breakfast.

Now, she too will have the amount of fat she's burning

measured for the next three hours, when she's not exercising.

But this isn't the first time that they've

undergone a test like this.

One week ago, Josh and Jess did almost the same thing,

except then they exercised after they'd had the liquid meal.

So now we should be able to see whether exercising before or

after eating is better for making your body burn fat.

And the results are astonishing.

Josh burned 10% more fat after he exercised on an empty stomach.

But for Jess, it was the reverse.

She burned more fat after she exercised on a full stomach.

Remarkably, it seems the secret of how to burn more fat might be

different for men and women.

It's an exciting new idea that has only

so far been seen in these carefully controlled laboratory conditions.

This is just one bout of exercise.

But people do repeated bouts of exercise.

They go to the gym on a regular basis

or they exercise several times a week.

This could have a cumulative effect

in terms of maximising your fat burning.

So we've teamed up with Adam to test his discovery in the real

world for the first time.

We want to find out if men and women really do burn fat differently.

Should men be exercising on an empty stomach

and women after they've eaten?

We'll find out later in the programme.

Still to come -

could having a big bum be good for you?

And allowing the blind to see again.

Honest to God, I felt like Christmas Day there!

But first...

..we're all keen to impress the friends and family we have

round during the festive season,

but with big meals come leftovers aplenty.

And not reheating them properly contributes to an impressive

surge in food poisonings at this time of year.

So how can we all avoid it?

Now, food shows don't normally deal with the subject of food poisoning.

But they've kindly allowed us to gatecrash their demonstration.

Hi, there. Good evening. Thank you for coming.

Are you having a good day? Good.

We all know we have to cook raw meat thoroughly,

but what are the rules for leftovers?

-Right. I have here a delicious curry I made a couple of days ago.

-OK.

Would you be happy to reheat it and eat it?

I'll pass on that one, then. Thank you.

So is it OK to be reheat it?

You think not? You'd go straight in the bin?

Would you happily heat it and eat it?

-Yes.

-You'd be happy?

-Yeah.

The Food Standards Agency suggest we only reheat our leftovers once.

Although you can actually reheat your leftovers as many times as you like,

as long as you make sure every morsel is piping hot all the way through.

Easy enough to do on the stove, but most of us use a microwave,

which leads to another common problem.

Microwaves create hotspots and dangerous cool spots in your food,

seen in red and blue on the thermal imaging camera.

And in the cool spots, bacteria can thrive.

So if you use a microwave, be sure to heat and stir and heat

and stir until you're satisfied it's really hot all the way through.

But there is one thing you should be cautious of reheating.

Do you think it's the rice or the chicken that's more dangerous?

-I would say the chicken.

-The rice.

-And you said rice?

-You hear a lot on TV about rice.

I think if I heated the chicken up, I'd be all right, but the rice...

My wife tells me this all the time.

Do not save rice under any circumstances.

There is a bacteria called Bacillus cereus. And that lives in rice.

And the thing about Bacillus cereus is that it also produces a toxin

and unfortunately the toxin is heat stable.

That means that you can heat it up, it will kill the bacteria,

but the toxin will get you.

So you can kill the bacteria,

but if they've already produced the toxin, that rice is going to

be poisonous, no matter how thoroughly you reheat it.

So put uneaten right in the fridge as soon as it's cooled down to

room temperature and only reheat it once.

So the rules are you can reheat food as many times as you like

if you heat it thoroughly all the way through.

The exception is rice.

Refrigerate that carefully and only reheat it once.

Do that and you should be safe. Trust me.

-Can't tempt you?

-No.

No, you're right. You can't.

Earlier in the programme, I set out to discover

whether the proteins from supplements could go straight into

our muscles, as the manufacturers would like us to believe.

And I was surprised to discover that they could.

And that the amount is higher with exercise.

But does that mean that taking

protein supplements gives us bigger muscles?

Well, to find out, we're going to do a big experiment of our own.

We've recruited 24 volunteers,

ranging in age from 20 to 67.

They all had a set of baseline measurements taken -

muscle strength, body fat composition,

and an ultrasound of their muscles.

Now, they're going to start on an eight-week training regime,

each gym session followed by an identical-looking drink.

But here's the twist.

While half of our volunteers are going to get a protein shake,

the other half are going to get a shake that appears to be

the same, but has no protein in it whatsoever - a placebo.

Lifting heavy weights three times a week should get their cells

releasing free radicals, signalling their bodies to repair

and boost their muscles.

But will drinking a protein shake make them grow stronger and bigger?

Even supervising scientist Dr Stuart Grey doesn't know

who's getting which shake...

but everyone's still happy with the regime.

I feel like I've got stronger, but that's just with the process

and working hard through the eight weeks.

But eight weeks later, after they're all retested,

-what do the results show?

-Good news.

Everyone got stronger, so you're all about on average 30% stronger

-than you were before you started.

-30%.

-30% stronger.

-You look better.

You looked pretty ropey before, but, you know.

And you're not only stronger,

you do have on average 1-2% more muscle mass than you did

when you started, so you've got bigger muscles and you're stronger.

What more could you want?

So the crucial question is,

did the people who had the real protein shake get stronger

or put on more muscle than the people who had the placebo?

-In short, no. Unfortunately not.

-Really?

-No.

No difference at all between the two groups. Everything exactly the same.

I must say I'm a little bit disappointed by that.

The extra that we were giving them

wasn't really making much difference at all.

Our results show that everyone got stronger, more able to lift weights

and everyone put on more muscle,

but there was no significant difference

between those that were given the protein supplements

and those that got placebo.

So, over our eight-week trial,

the protein shakes did not give them a benefit. This seems baffling.

After all, earlier in the programme, I saw first-hand how protein

I'd consumed in a shake went directly into my leg after exercise.

But, as Stuart explains, our diets are full of protein

and adding extra doesn't seem to help us build muscle.

There's a limit to what the body can cope with.

About 20 to 30 grams is as much as your body can take in,

in a single consumption.

Anything more, you're really going to burn it as energy,

oxidise it, you're going to store it as, most likely, fat

or you're just going to pee it out in the urine,

so it's not going to get into the muscle.

So once you've got enough protein on board, basically,

-anything else is turned into urine, fat or energy.

-Yeah, yeah.

So, it's not going to do what you want it to do.

Who's going to go and buy a fancy protein drink and take it?

-You're still going to do it.

-Get out!

-There's always one.

-Very nice, very nice.

So whilst protein from supplements can go directly into your muscles,

taking them isn't actually going to help you build any more muscle

because as long as we get enough protein in our normal diet,

any extra is just a waste.

The truth is, that none of us need to drink these protein supplements.

If you're getting extra protein in that way,

you're probably just making very expensive urine,

so if I were you I'd cut out the middleman.

Protein shakes aren't the only drinks designed for gym bunnies

that made their way onto supermarket shelves.

Energy drinks are big business.

We get through about 45 million litres of the stuff every year.

Now, they claim to keep you energised and rehydrated,

so what's actually in them?

And are they worth the money?

I'm going to show you how easy it is to make your own, virtually for free.

The first and most obvious thing you need is water.

Here is about half a litre of ordinary tap water.

That's about the same amount as you'd find in one of these bottles.

The next magic ingredient is sugar and each of these contains

the equivalent of six to eight teaspoons of sugar.

And because that tastes pretty unpleasant,

I think I'll add a little splash of orange squash.

If you are really working hard and sweating like crazy,

then you are going to be losing electrolytes

and how do you replace them?

Well, you can do so with about an eighth of a teaspoon of this stuff,

which is sodium chloride, also known as salt.

And there you have it.

Michael Mosley's sports drink, made out of sugar, water,

salt and just a hint of flavouring. Costs virtually nothing.

The only remaining question is

should I drink it before or after exercising?

Earlier in the programme, we discovered that the secret

of how to burn more fat might be different for men and women.

Our laboratory test on a brother and sister pair suggested that

men burn more fat after they've exercised on an empty stomach,

women on a full stomach.

It's a new discovery

and it's never been tested in the real world until now.

We've recruited a group of 31 volunteers.

They're about to embark on a four-week experiment.

Before they start, Adam Collins is taking a baseline measurement

of how much fat their bodies are burning when they're at rest.

Now it's time to split them into two groups.

Both will be given an identical breakfast -

a special drink with a precisely controlled number of calories.

Group 1 will have theirs before they exercise.

Group 2 will have theirs after they exercise.

Both groups will do exactly the same exercise programme -

a combination of high-intensity training,

Zumba, and spin classes, carried out first thing in the morning.

We want to test the idea that men can burn more fat

if they exercise on an empty stomach, women on a full stomach.

After four weeks of exercise, we'll take the same measurements again

to see if there's been any change in how much fat they're burning.

We want to see if shifting exercise to before or after eating

will have any effect in the longer term.

Find out later in the programme.

There are some medical inventions which, to me,

still feel like science fiction - the bionic eye, for example.

Well, surgeon Gabriel Weston has been following the story

of a woman who is about to have one

of the world's most advanced artificial eyes.

When she was just five years old,

Rhian Lewis was diagnosed with retinitis pigmentosa...

..a disease that damages the light-sensitive cells in the retina.

Her right eye is now completely blind...

..and her left eye is virtually without sight.

It's a bit like if somebody's putting a dimmer switch off

ever so gradually and the dimmer switch is going lower and lower

and lower and the light is going less and less.

It's been maybe eight years since I've had any idea

what my children look like and I certainly don't know how I've aged.

There is no cure for this disease,

but a treatment being trialled in Oxford

could give Rhian back some of her sight.

Surgeons are going to replace the damaged retinal cells

with an electronic chip.

If I had a little bit more sight,

I'd have a little bit more confidence and I might venture out.

That's my big thing.

Rhian is about to become the very first patient

in an NHS-funded trial

which is looking at the most advanced kind of retinal implant -

something that most people are beginning to know

as the bionic eye - and if it works, it could restore elements

of her vision that she thought that she had completely lost for ever.

The implant has been developed in Germany and the delicate task

of positioning it will fall to Professor Robert MacLaren.

We've got to get the implant in exactly the right position

at the back of the eye, but we also need to avoid damaging the nerve.

We need the nerve to send the signals from the implant

back into the brain

and that nerve is less than a millimetre from the optimal position

of the chip and if we move the chip a millimetre the other way,

we may not get very useful vision.

So it is absolutely critical and that's what takes a long time -

it's getting that position exactly right.

This entire process will take about ten hours.

Already the ENT surgeon has implanted a power supply

for the device behind Rhian's ear.

Now, Robert and his assistant, Tom Edwards,

can begin the intricate job of inserting the chip.

The chip is only three millimetres wide and the delicacy required

to manoeuvre it into place is extraordinary.

This is a very tense moment in the surgery.

The guide wire has been removed,

leaving the implant exactly where it needs to be, and Tom's holding it

there, absolutely still, so Robert can fix it in place.

Brain surgeons are always given all the credit

for doing the most delicate, difficult work

and, to my mind, these guys are absolutely up there.

The operation has gone well, but it's only a few weeks later -

when Rhian's eye has healed -

that she'll know whether the implant works.

It's a big moment, not just for her, but for the whole team.

-Yes, there is a pulse rather than a flash.

-Uh-huh?

-So shall I go down a bit further?

-You can.

At first, Rhian will only be able to see flashes of light.

That's because her brain has to learn how to see again.

What Rhian and others are trying to do is to reactivate

part of the brain that hasn't been doing anything

for the last ten years or so,

and it's almost like a rehabilitation where, you know,

they're learning to use something again that they hadn't had before.

To test for meaningful vision, the team want to know

if Rhian can pick out the contrasting hands on this clock.

I'm thinking 12...

..three...

-Mm-hm.

-I think three is longer.

-Have a feel.

-Oh, it is.

Oh, my God!

-Spot on.

-I got it right.

You did. Well done.

For the first time in 16 years,

she's got some vision in her right eye.

-Honest to God, I felt like Christmas Day there.

-That's perfect.

It's a great start and, over the next few months,

Rhian's brain will get better and better

at interpreting the signals to form an image.

I always think it's very nice

to compare that to very early TV pictures -

very, very grainy, black-and-white, just an outline of things,

moving and coming and going, compared to what we see,

that is a considered to be a low level of vision.

For someone who's completely blind, the ability to see people moving

around in front of them, and shapes, is an actual life-changing event.

-Three small, 12 big.

-OK.

I really didn't know what to expect, but when something actually happens,

you think, "Oh, my word," you know, just amazing.

It's now been six months since the operation

and although it's still early days, Rhian's brain is starting

to be able to understand the signals from her eye in three dimensions.

-So here?

-Yeah. Can you find an edge to it?

Oh, my God!

The surgery is making her dream of mobility come true.

Well, it's a mixture of relief and disbelief, really,

that we've been able to give her some vision back.

If our results continue to be as promising as they've been so far,

then it's likely that in the future

this device may be available on the NHS. That's the hope.

-No way.

-Exactly on it.

-No way.

-Exactly on it.

Could you just describe for me what it's felt like for you?

Well, I was hoping my smile would tell it all

because just the sensation of...

You're not completely helpless, that you can usually find

an edge of a wall and it's... Oh, I really can't put it into words.

I just felt elated.

Oh, my God.

Seeing Rhian using this device has been fantastic.

The difference it has made in just six months is astounding.

Now, it sounds like not very much to those of us

who can see everything,

but, in fact, for the thousands of people who suffer from these sorts

of debilitating eye diseases,

this technology is offering incredible hope.

There's more information on this and all the other items on the programme

on our website at...

At this time of year, we're thinking about getting healthier,

but how do we know what to do?

We're told something is good for us, then too much is bad,

so what are the limits? When can you have too much of a good thing?

I want to find out the evidence behind some of the things

that we hear so much about in the press...

..exercise, body fat, alcohol, meat.

This time I'm looking at fat.

How much is too much?

What are the best ways of measuring it

and could there be some forms of fat that are actually good for you?,

Government guidelines centre around a height-to-weight ratio

called body mass index, or BMI.

A BMI above 25 is considered unhealthy,

but BMI had been criticised as a poor measure of obesity.

And is all excess body fat a bad thing?

I've come to hear the opinions of two leading obesity experts

with very different points of view.

Professor Nicholas Finer thinks that too much body fat

is almost always a bad thing.

I would have no doubt in saying that there will be benefits

from losing weight.

However, Professor Fredrik Karpe believes that in the right place,

the more fat, the better.

The wider the hips, the more healthy you are,

the less diabetes you have, the less cardiovascular disease you have.

So how have they come to such different conclusions?

I want to hear their evidence.

Fredrik Karpe is Professor of Metabolic Medicine

at the Oxford Centre for Diabetes, Endocrinology and Metabolism.

His research focuses on the effects of different types of fat tissue.

The assumption is that losing weight is always a good thing.

-Yes, that is an assumption.

-And it's one you're challenging?

I would challenge that, yes.

There is actually quite good evidence that

if you are overweight and you have no problems,

metabolic problems, your have no benefit from losing weight.

Well, that is quite a radical thought.

Oh, I wasn't expecting that, right.

Well, I don't know why there's this vilification of fat tissue,

because it's actually an absolutely necessary and vital organ

for the human body, and fat on the leg, around the gluteal area,

is extremely good at storing fat in a very safe way, so it's tucked away

and isn't filling fat into other parts of the body.

OK, so if you've got fat around the legs

and the thighs and the bottom, is that fat good or neutral?

I think it's good and there is a good body of evidence

to suggest that it is actually beneficial to have that fat.

It's very paradoxical. The more of it you have, the better it is.

OK, that is paradoxical

because the assumption is that all fat is bad beyond a certain point

and you're saying that if you put on fat down here, it is positively good,

-and is that true for men and women?

-Yes, it is.

Do you actually have evidence that that is good for you?

The evidence comes from large epidemiological studies,

so it's fairly consistently been demonstrated

that the wider the hips, the more healthy you are,

the less diabetes you have, the less cardiovascular disease you have.

-I'm aware that if you have a large waist...

-Yes?

..then that puts you at significant risk of developing type 2 diabetes,

but if you have a large waist but you have even larger hips,

-would you that suggest your diabetes risk goes down?

-Yes.

There is at least one study strongly suggesting that,

and we have our own unpublished data showing the same thing,

so I think one can make a good case for that claim.

So, if you're a woman and you have a BMI of, say, 28, 29,

you have quite bit hips compared to your waist,

is there any evidence that if you lose weight

that might actually be bad for you?

No, that study has not been performed,

so that evidence is not there,

but you can also turn around the question and say,

well, that woman with a BMI of 30 and the wide hip,

possibly doesn't have any complications

of being moderately overweight, so where is the evidence to lose weight

when you have no complications of your obesity?

So, Professor Karpe isn't convinced of the benefits

of always losing weight, even if your BMI is a bit high,

and he believes that fat on the bum and thighs is actually good

for us and can cancel out some of the bad effects of fat on the belly.

It's a pretty radical view and not one that's shared by everyone.

Professor Nicholas Finer is a consultant in Endocrinology

and Bariatric Medicine at University College Hospital, London.

So if you have a BMI over 25, you're technically overweight -

is losing weight always a good thing?

Well, I would say that, yes, it is, except perhaps in the elderly,

and it may not be a good thing in people who are already ill.

So what are the benefits of losing weight

if you have a BMI of, say, over 30?

There are enormous benefits and we have very good evidence of this.

We know that the risks of diabetes are reduced by as little

as a 5% weight loss.

We know that the risks of heart disease,

of breathing problems at night, are improved.

We know that, actually, quality of life improves,

so the evidence for the benefits of weight loss,

I think, is overwhelming.

Where it is problematic

-is in that normal range and slightly overweight range.

-So 25 to 30?

-Yeah.

And what we do know is that fat in different places

-has different risks.

-And where is the worst place to have it?

Almost certainly the worst place to have it is in your belly.

That is the wrong type of fat, which causes consequences

such as diabetes, hypertension, fatty liver disease.

-Do you think that some fat can be healthy?

-Oh, absolutely.

I mean, first of all, we need energy stores in our body,

so we need some fat, so storing fat is necessary,

but we don't need as much as most of us have.

In terms of, say, fat on the buttocks and the lower part,

do you believe that they're protective?

We're not in a position, if you like, to do a prospective study

where we get people to either store fat down there

or store fat in the belly and that would really be,

it would seem to me, the way to answer that question.

And in terms of the hip-to-waist ratio,

do you ever measure it in your patients?

At an individual clinical level, I don't like waist-to-hip ratio

and the reason for that is that a waist-to-hip ratio doesn't change

when you lose weight, because if you lose weight from your waist

and from your hips, it comes down.

And in terms of your age, I've seen studies which suggest that

after the age of, say, 65, then a BMI of 25 to 30 is possibly protective.

Yes.

Things change as you get older.

OK, as you get older, the ratio of fat to lean tissue may change,

so people may have not only excess fat,

but particularly low levels of lean tissue.

-Yes, muscle.

-Yes, muscle and bone.

And if these people lose weight, they may lose some fat,

but they may end up with unhealthily low levels of lean body mass.

So you don't think there's a real paradox there at all?

The problem is

when you start applying this to the population as a whole.

We know that as BMI goes up, the risk of diabetes,

heart disease, etc, all increase,

and there are large numbers of prospective studies that show that.

We know that weight loss improves all of those parameters.

Professor Finer believes total fat loss is always a good thing

if you are obese by a measure of BMI,

but BMI is the best measure we currently have,

and you can't argue with the links between BMI and disease risk.

So, after hearing the evidence on both sides, time for me

to decide what I believe.

Well, that was absolutely fascinating.

Professor Karpe obviously believes that if you're pear-shaped,

there are lots of advantages.

Professor Finer thinks it is absolutely pointless

measuring your waist and your hips.

I think I go with Professor Karpe on this one.

As to how much fat is too much, well, both of them agreed -

it depends on whether it is making you sick,

then that is too much and you should do something about it.

Over the past month, we've been running an experiment

to test a brand-new theory, that men burn more fat through the day

if they've exercised on an empty stomach

and women if they've exercised after eating.

Three mornings a week, two groups of volunteers

have been on an identical programme of exercise.

They've also had an identical liquid breakfast -

one group before they exercised and the other group after.

-How did you find the whole process?

-I enjoyed it, yeah.

Zumba on a Friday morning is definitely an eye-opener.

Felt better, slept better, performed better.

-What time were you waking up in the morning?

-About 6.15 in the morning.

-Do you think you'll stick to that?

-No.

Prior to this, I probably had the fitness levels of a pork scratching,

-but now I feel like I'm much fitter.

-Yeah?

Much more lively, a healthier pork scratching.

So our volunteers are certainly feeling fitter,

but is there any difference in how they're burning fat?

Before our volunteers started the experiment, Adam Collins took

a baseline measurement of how much fat they were burning at rest.

Now he's repeating that measurement.

Each volunteer will find out if they're burning more or less fat

than when they started.

It's time for the results.

First up, the group who exercised after eating.

Men on my left and women on my right. Now open your envelopes.

Those of you that have got the same, so you burnt the same amount of fat,

just stay where you are.

Those of you that were worse, take a step back.

Those of you that were better, take a step forward.

Most of the men are now burning less fat

compared to when they started,

whereas most of the women are burning more.

Group 2, you're on.

This group exercised on an empty stomach.

Compared to the last group, the men are burning more fat

and the women are burning less.

On average, the women were nearly 22% better off

exercising after eating

and the men were 8% better off exercising on an empty stomach.

So what can explain the difference between the sexes?

Since this is a brand-new finding, we're not yet sure,

but it may have something to do with the way our bodies handle

the different types of food we use as fuel - carbohydrates and fat.

Both men and women will store carbohydrate in muscle

and men have more muscle than women,

so they have got a greater capacity to store and utilise carbohydrates.

So they're really designed to burn carbohydrate preferentially,

compared to women.

So men are built to burn carbs and if they eat before they exercise,

they'll have such a ready supply of carbohydrates

that that's mainly what their bodies will use

and the effects last throughout the day,

so to avoid this and burn more fat instead,

they need to do their exercise on an empty stomach.

And the women?

Women have more body fat and less muscle mass,

so women, if you feed them carbohydrate,

they still will be able to burn fat

because they're better designed to burn fat during exercise.

And our results suggest that women actually burn more fat

if they've done exercise after eating.

# The female of the species is more deadly than the male... #

What I've seen here has been really startling.

When it comes to burning fat, it seems what's good for the goose

isn't necessarily good for the gander.

Women should definitely eat before they exercise

and men should eat after.

Getting this right can help us to lose that spare tyre

and become healthier into the bargain.

So when it comes to exercise, we've discovered some very useful cheats.

It's important to keep your muscles strong, as well as getting a workout,

but you can do that with just a few well-spent minutes at home.

Protein supplements and fancy sports drinks are a waste of money.

And when you do your workout - if you're a woman, do it after eating,

whilst if you're a man, do it on an empty stomach.

That way you'll be burning more fat for many hours afterwards.

That's it from Manchester.

Next time, we're in Surrey where we're finding out

if simply changing the time of day you eat can make you healthier...

..asking could diet products be making you fat,

and how much is too much alcohol?

# I just made an appointment for a special rendezvous

# To see a man of miracles and all that he can do

# Doctor, I want you

# Mmm, my doctor wanna do

# I can't get over you

# Doctor, do anything that you wanna do. #